package com.wf.smartcomm.server.util;

import javax.crypto.Cipher;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.security.Key;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.MessageDigest;
import java.security.SecureRandom;

public class RSAUtils {
	/** 指定加密算法为DESede */
	private static String ALGORITHM = "RSA";
	/** 指定key的大�?*/
	private static int KEYSIZE = 1024;
	/** 指定公钥存放文件 */
	private static String PUBLIC_KEY_FILE = "E:\\roadbarServer\\PublicKey";
	/** 指定私钥存放文件 */
	private static String PRIVATE_KEY_FILE = "E:\\roadbarServer\\PrivateKey";

	/**
	 * 生成密钥�?
	 */
	private static void generateKeyPair() throws Exception {
		/** RSA算法要求有一个可信任的随机数�?*/
		SecureRandom sr = new SecureRandom();
		/** 为RSA算法创建�?��KeyPairGenerator对象 */
		KeyPairGenerator kpg = KeyPairGenerator.getInstance(ALGORITHM);
		/** 利用上面的随机数据源初始化这个KeyPairGenerator对象 */
		kpg.initialize(KEYSIZE, sr);
		/** 生成密匙�?*/
		KeyPair kp = kpg.generateKeyPair();
		/** 得到公钥 */
		Key publicKey = kp.getPublic();
		/** 得到私钥 */
		Key privateKey = kp.getPrivate();
		/** 用对象流将生成的密钥写入文件 */
		ObjectOutputStream oos1 = new ObjectOutputStream(new FileOutputStream(
				PUBLIC_KEY_FILE));
		ObjectOutputStream oos2 = new ObjectOutputStream(new FileOutputStream(
				PRIVATE_KEY_FILE));
		oos1.writeObject(publicKey);
		oos2.writeObject(privateKey);
		/** 清空缓存，关闭文件输出流 */
		oos1.close();
		oos2.close();
	}

	/**
	 * 加密方法 source�?源数�?
	 */
	public static String encrypt(String source) throws Exception {
		//generateKeyPair();
		/** 将文件中的公钥对象读�?*/
		ObjectInputStream ois = new ObjectInputStream(new FileInputStream(
				PUBLIC_KEY_FILE));
		Key key = (Key) ois.readObject();
		ois.close();
		/** 得到Cipher对象来实现对源数据的RSA加密 */
		Cipher cipher = Cipher.getInstance(ALGORITHM);
		cipher.init(Cipher.ENCRYPT_MODE, key);
		byte[] b = source.getBytes();
		/** 执行加密操作 */
		byte[] b1 = cipher.doFinal(b);
		BASE64Encoder encoder = new BASE64Encoder();
		return encoder.encode(b1);
	}

	/**
	 * 解密算法 cryptograph:密文
	 */
	public static String decrypt(String cryptograph) throws Exception {
		/** 将文件中的私钥对象读�?*/
		ObjectInputStream ois = new ObjectInputStream(new FileInputStream(
				PRIVATE_KEY_FILE));
		Key key = (Key) ois.readObject();
		/** 得到Cipher对象对已用公钥加密的数据进行RSA解密 */
		Cipher cipher = Cipher.getInstance(ALGORITHM);
		cipher.init(Cipher.DECRYPT_MODE, key);
		BASE64Decoder decoder = new BASE64Decoder();
		byte[] b1 = decoder.decodeBuffer(cryptograph);
		/** 执行解密操作 */
		byte[] b = cipher.doFinal(b1);
		return new String(b);
	}
	
	 public static String string2MD5(String inStr){  
	        MessageDigest md5 = null;  
	        try{  
	            md5 = MessageDigest.getInstance("MD5");  
	        }catch (Exception e){  
	            System.out.println(e.toString());  
	            e.printStackTrace();  
	            return "";  
	        }  
	        char[] charArray = inStr.toCharArray();  
	        byte[] byteArray = new byte[charArray.length];  
	  
	        for (int i = 0; i < charArray.length; i++)  
	            byteArray[i] = (byte) charArray[i];  
	        byte[] md5Bytes = md5.digest(byteArray);  
	        StringBuffer hexValue = new StringBuffer();  
	        for (int i = 0; i < md5Bytes.length; i++){  
	            int val = ((int) md5Bytes[i]) & 0xff;  
	            if (val < 16)  
	                hexValue.append("0");  
	            hexValue.append(Integer.toHexString(val));  
	        }  
	        return hexValue.toString();  
	  
	    }  
	  
	    /** 
	     * 加密解密算法 执行�?��加密，两次解�?
	     */   
	    public static String convertMD5(String inStr){  
	  
	        char[] a = inStr.toCharArray();  
	        for (int i = 0; i < a.length; i++){  
	            a[i] = (char) (a[i] ^ 't');  
	        }  
	        String s = new String(a);  
	        return s;  
	  
	    }  
}